This invention relates, in general, to molds and molding processes and is specifically directed to a method and apparatus for applying release agents to surfaces of molds.
The purpose of release agents applied to mold surfaces is, of course, well known but the proper application of the release agent to the mold surface has been difficult to achieve. Often the release agent was not applied uniformly across the surface of the mold with the result that the molded article, such as a composite article, sometimes stuck totally or in part to the mold surface. This non-uniformity of distribution of the coating was due to a number of things--partial or complete clogging, intermittent clogging, of the applicator (spray-gun) used to apply the release agent, a degraded release agent, or simply the inability to determine the non-uniformity of the coating, visually or otherwise. Thus, there is a need to measure the amount of release agent applied to a mold surface in a quantitative manner and it is one of the objects of this invention to provide such a method.
It will be apparent to those skilled in the art that, in practicing such a method, robotics is possible and it is another object of this invention to provide an apparatus by which the proper amount of release agent is automatically applied to a mold surface.
In addition to the inability to properly apply the release agent to the mold surface, prior methods suffered under the drawback of the degradation of the release agent before and during application, as mentioned above. This degradation decreased and release characteristics of the release agent, or inactivated the release agent, thus inhibiting the proper release characteristics of the coating after cure.
It is therefore another object of this invention to provide a method and apparatus which provides for release agent degradation detection and correction and which detects and corrects this degradation in-line (in real time) so that this latter method may also be a part of the automation of the first method.
In the practice of the foregoing method and apparatus a completely automatic mold release cell is needed which will take molds, coat them with a release agent, bake (cure) them, or recoat them and rebake them the appropriate number of times, before releasing the properly treated molds. This would completely release human involvement in the application of the desired amount of release agent onto the mold and in the transport of the mold to and from oven areas where the release agents are cured. Thus it is still another of object of this invention to provide such an apparatus.